Construction machines include those which have a pair of tracks which are drivable by a drive device such as an engine. Such construction machines also include bulldozers which are designed for use for earth moving applications. The use of tracks provides the advantage of an optimum grip while the surface contact of the tracks is improved with respect to other alternatives such as wheels.
Construction machines usually comprise an operator's cab in which an operator of the construction machine can sit while he performs the required operations during the use of the construction machine. Such operator's cabs include at least partially open cabs and closed cabs. Recent developments led to constructions in which the operator's cab is completely closed in order to prevent dust from entering the operator's cab and to allow the option of an efficient air conditioning of the inner space of the operator's cab.
The accessibility of the operator's cab when applied to construction machines is usually a problem. For providing a completely closed operator's cab, a door will be provided which can be opened in order to access the operator's cab. Due to the substantive height of the operator's position in the operator's cab, the operator has to climb up to the level which allows him to enter the operator's cab.
In a particular application in which the construction machine employs a pair of tracks or crawler track chains on both sides, it is widely accepted that the operator steps on the upper area of one of the tracks, opens the door and enters the operators cab. However, this accepted solution is obviously not satisfactory due to the fact that such a course for entering the operator's cab is unacceptable in view of safety requirements. Moreover, such machines usually are used in earth moving applications such that the tracks will be covered by a substantive amount of dirt which results in an unacceptable entry of dirt into the inner space of the operator's cab which should be avoided as much as possible.